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Intel
82865G/82865GV GMCH Datasheet
3
Contents
1
Introduction
...........................................................................................................15
1.1
Terminology...................................................................................................16
1.2
Related Documents .......................................................................................17
1.3
Intel
865G Chipset System Overview..........................................................18
1.4
Intel
82865G GMCH Overview ....................................................................20
1.4.1
Host Interface....................................................................................20
1.4.2
System Memory Interface.................................................................20
1.4.3
Hub Interface ....................................................................................21
1.4.4
Communications Streaming Architecture (CSA) Interface................21
1.4.5
Multiplexed AGP and Intel
DVO Interface.......................................21
1.4.6
Graphics Overview............................................................................22
1.4.7
Display Interface ...............................................................................24
1.5
Clock Ratios...................................................................................................24
Signal Description
..............................................................................................25
2.1
Host Interface Signals....................................................................................27
2.2
Memory Interface...........................................................................................30
2.2.1
DDR SDRAM Channel A ..................................................................30
2.2.2
DDR SDRAM Channel B ..................................................................31
2.3
Hub Interface .................................................................................................32
2.4
Communication Streaming Architecture (CSA) Interface...............................32
2.5
AGP Interface ................................................................................................33
2.5.1
AGP Addressing Signals...................................................................33
2.5.2
AGP Flow Control Signals ................................................................34
2.5.3
AGP Status Signals ..........................................................................34
2.5.4
AGP Strobes.....................................................................................35
2.5.5
PCI Signals–AGP Semantics............................................................36
2.5.5.1
PCI Pins during PCI Transactions on AGP Interface ........37
2.5.6
Multiplexed Intel
DVOs on AGP......................................................37
2.5.7
Intel
DVO-to-AGP Pin Mapping.......................................................39
2.6
Analog Display Interface................................................................................40
2.7
Clocks, Reset, and Miscellaneous Signals....................................................41
2.8
RCOMP, VREF, VSWING Signals.................................................................42
2.9
Power and Ground Signals............................................................................43
2.10
GMCH Sequencing Requirements.................................................................44
2.11
Signals Used As Straps.................................................................................45
2.11.1 Functional Straps..............................................................................45
2.11.2 Strap Input Signals............................................................................45
2.12
Full and Warm Reset States..........................................................................46
Register Description
..........................................................................................47
3.1
Register Terminology.....................................................................................47
3.2
Platform Configuration Structure....................................................................48
3.3
Routing Configuration Accesses....................................................................50
3.3.1
Standard PCI Bus Configuration Mechanism ...................................50
3.3.2
PCI Bus #0 Configuration Mechanism..............................................50
3.3.3
Primary PCI and Downstream Configuration Mechanism.................50
3.3.4
AGP/PCI_B Bus Configuration Mechanism......................................51
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